Vinyl chloride polymer plasticizer with adducts of fumarates and alkylene esters of long chain fatty acids



VINYL CHLORIDEPOLYMER 'PLASTICIZER WITH ADDUCTS" OF. ALKYLENE ESTERS'OFLONG CHAIN FATTY ACIDS Joachim Dazzi, Dayton, Ohio, assignor to-Monsanto Chemical Company, -St. Louis, -Mo., a-corporation of Delaware'No Drawing. Original application August 28, 1950, Se-

rial-No. 181,947,. now Patent No. 2,782,227,-dated United States 51ccFebruary 19,1957. Divided andthisapplication tober 12, .1956,- SerialNo. 615,457

'Claims. (Cl."26.0'31'.8)

The present invention relates to resinous compositions and moreparticularly with plastici zed vinyl chloride polymers.

I have found that particularly valuable as plasticizers for vinylchloride polymers are-polycarboxylates having thegeneral formula:

TLC'HIOO'CX in which T is analkenyl radica1:offrom 910 23 carbon .atomsYis selected from theclassiconsisting: of hydrogen and the methylradicaL aIk-is analkyl radicalloftrom 1 to 6 .carbomatoms, .X isselected fromthe class consisting of alkand the radica1-CY:CY.COO.alk,and n is a number of from 1 to 3.

.Polycarboxylates of the above formula maybe obtained by the additionreaction-of: anesterofa long-chain alkenol with an a eolefinic.dicarboxylic anhydride andesterifica- .tion oftheeresultinghadditionproductor by the addition reactionofsaidralkenol'with a dialkyl ester of an acyclic a, 3-olefinicdicarboxylic acid. I

Esters of long-chainedalkenols which-are employedtor the preparation ofthe present polycarboxylic compounds have the generaiforrnula'T.CH.OOC.Z in whichTis an a'lkeniy'l radicalfo'f from 910 23 carbon atomsand Z is 1 selected fromthe class consisting ofalkylradicals offrom '1to 6 carbon atoms and the radical CY:C YCOO.a1kyl. As illustrative :ofesters having this .general.forn1ula may be mentioned undecenyl and-oley'.l.acetate,- propionate,

'butyrate, -.isobutyrate, n-valerate, isovalerate, n-hexoate,

furnarate, maleate, citraconate, etc.

Acyclic afi-ole'finic dicarboxylic esters which add with .the abovelong-chained alkenyl esters to yield the'present polycarboxyliccompounds have the formula:

in which Y is "selectedxfrom ithe class eonsisting ofrhydro :gemandthemethyl radical'and alk denotesan alkyl radiample, -dimethyl, dibutyl.or. dihexyl maleate; diethyl,

dibutyl or .diamyl iumarate; dimethyl,diisopropyl' 'or di- Useful:pdlycarboxylatesimay be. prepared :by -the addition: reaction of :theshigherialkenyl esters with mal'eic' an- ;hycln'deandsubsequent'esterification, thus:

,propyl' citraconate; mono-methyl in aleate, mono-ethyl fumarate,mono-:ethy1:citraconate, etc. 7 e

2,833,739 fPate nted May 6, 1 958 alkyl radical.

Here thereprob ablyiioccurs"an ester' interchange Y.G.GO0.-alk Y H ,l+alk..0OO.OH1'1 'Y.G.COOJCHiT-i-alkCOQalk Y. .COOalk 1 I Y;C.COO.alk' Iand the mixed 'dicarboxylate thus obtained further reacts'as follows:' 1

Y. C.000.alk

'Y.C.C-OO'CH2T v *f'rt ioooaik Y.OH.COO.alk lilWhlCh n is a number offrom 1 to 3. i The formation of 1:'1,1:2or"1:'3"oleyl esterdicarboxylateadducts is a function of reactant .pr'ope'rtionsgof heatingtime and temperature and catalyst. Employin equimolar quantities of thereactants, or an excess'df the oleyl ester, ester-interchange results."With about' two moles'of the dicarbo xylate, the product is generallya"1i'1 pound, short heating, say, for'tro'ma"'few"hoursto' ten hours attemperatures'of from, say, 200 C. to 220 C., generallyresults inthe-formation of a preponderance of the 1:1 adduct. With longerheating"time,'say, aheating time of from 10 to 48 hours a'prepondera'nceof the higher ratio adducts are formed. Thehigher"ratio"adducts are also formed in preponderant quantities'Whe'nemployinga shorter heating -time,"but in this case higher temperaturesare required, i. -e., temperatures"of'from,

say, 220 'C.=to 280 C., depending upon there'activities anddecomposition points of the reactants.

Because of uncertainty concerningrthe positionatwhich the dicarboxylicresidue is attached to'th'e' alkenyl 'es'te'r, the presently usefuladducts will be hereinafter referred to without stipulating the positionof the introduced car- :boxy groups.- For, convenience, however,wlrn'fd'ealing Wiih-flddHCtS' prepared 'from, 'e.. g.,inaleic"anliydride or multaneously a high degree of low temperatureflexibility,

very good temperature stability and good mechanical strength to thesepolymers. The present esters are compatible with vinyl chloride polymersand show no exudation of plasticizer even at plasticizer content of upto 50 percent.

Although the quantity of plasticizer will depend upon theparticularpolymer to be plasticized and upon its molecular weight, it is generallyfound that compositions having from 5 percent to 50 percent by weight ofplasticizer will, in most cases, be satisfactory for general utility.The good flexibility of the plasticized compositions increases withincreasing plasticizer concentration.

In evaluating plasticizer efliciency use is made of the followingempirical testing procedures:

C0mpatibility.Visual inspection of the plasticized composition isemployed, incompatibility of the plasticizer with the polymer beingdemonstratedby cloudiness and exudation of the plasticizer.

Hardness.-A standard instrument made by the Shore Instrument Company isused for this determination and expresses the hardness in units from 1to 100. The hardness of the composition is judged by its resistance tothe penetration of a standard :needle applied to the composition under astandard load for a standard length of time.

Low temperature flexibility.Low temperature flexibility is one of themost important properties of elastomeric vinyl compositions. While manyplasticizers will produce flexible compositions at room temperature theflexibility of these compositions at low temperatures may varyconsiderably, i. e., plasticized polyvinyl chloride compositions thatare flexible at room temperature often become very brittle and uselessat low temperatures. Low temperature flexibility tests herein employedare according to the Clash- Berg method. This method determines thetorsional flexibility of a plasticat various temperatures. Thetemperature at which the vinyl composition exhibits an arbitrarilyestablished minimum flexibility i s defined as the low temperatureflexibility of the composition. This value may also be defined as thelower temperature limit of the plasticized compositions usefulness as anelastomer.

Volatility.-Just as a decreasein low temperature often results indecreased flexibility of a plasticized polymer composition so does adecrease in plasticizer concentration when caused by volatilization ofthe plasticizer. Hence, plasticizers which are readily volatilized fromthe plasticized composition as a result of aging or heating areinefiicient because upon volatilization the plasticized compositionsbecome stiff and hard. The test for plasticizer volatility hereinemployed isthat described by the AmericanSociety for Testing Materialsunder the designation D-744-44T.

Water resistanice.-The amount of water absorption and the amount ofleaching that takes place when the plasticized composition is immersedin distilled water for 24 hours is determined.

The invention is further illustrated, but not limited, by the followingexamples:

Example 1 A mixture consisting of 310.5 g. (1 mole) of oleyl acetate,122.5. g. (1.25 mole) of maleic anhydride and 1.55 ml. of triphenylphosphite was brought to a temperature of 115 C.,.and then during aperiod'of 5 hours, in a nitrogen atmosphere, and under reflux, themixture was stirred at a temperature of from 198 C. to 220 C. The lattertemperature did not reach 220 C. until the last hour of heating. Thereaction mixture was treated with 7.5 g. of clay and 2.5 gof a filteraid for 30 minutes and then with 3.5 g. of charcoal. After filtering andwashing the residue the filtrate and the washings were combined, dried,and vacuum distilled to remove material boiling up to 210 C./1.01.5 mm.The residue (173 g., n 1.4779), comprising the anhydride ofsubstantially pure (1',2'-dicarboxyethyl)octadecenyl acetate had asaponification equivalent of 133.5 (calcd. 139.3).

Conversion of this anhydride to the dibutyl ester of(l',2'-dicarboxyethyl)octadecenyl acetate was effected as follows: Amixture consisting of 122.4 g. (0.3 mole) of the anhydride, 0.9 mole ofn-butanol, g. of benzene, and 5 ml. of 96% sulfuric acid was stirred for7 hours, during which time, 9.0 cc. of water was collected by means ofthe Dean-Stark type water-trap with which the reaction vessel wasequipped. The reaction mixture was washed with 700 ml. of water, treatedwith 50 ml. of 5% aqueous sodium bicarbonate and then washed to neutral.Vacuum distillation was employed to remove low. boiling material andsubsequent fractionation gave the substantially pure dibutyl(l',2'-dicarboxyethyl)octadecenyl acetate, B. P. 240 C./0.6-0.9 mm., n1.4610.

Example. 2

A mixture consisting of 124.2 g. (0.4 mole) of oleyl acetate and 1.0mole of diethyl fumarate was charged to a vessel which was equipped witha Vigreux column and a Dean-Stark type trap fitted with a condenser; andthe mixture was refluxed for about 14 hours. During this period 32.6 g.of a low boiling liquid, B. F. 70-90 C., n;; 1.3842 (mostly ethylacetate) was collected in the trap. An additional 0.4 mole of diethylfumarate was then added to the reaction vessel, and the reaction mixturewas again refluxed for 30 hours at a temperature of 230 C. to 245 C.There was thus collected an additional 6.3 g. of lowboiling material.Distillation of the product removed 67.4 g. of diethyl fumarate and gaveas residue 245.5 g. of a material, which while bubbling nitrogen throughit, boiled above an oil-bath temperature of 220 C. to 230 C./ 0.3 mm.,had a saponification equivalent of 136.1, 12 1.4760 and a molecularweight of 644.5. Based on the recovered diethyl fumarate, 2.52 moles ofdiethyl fumarate have reacted, one mole of which participated in thecross-esterification and 1.52 moles of which added to the oleyl radical.Accordingly, the present product is mono-ethyl mono-oleyl fumarate inwhich some of the hydrogens of the oleyl radical has been substituted bybis( 1,2'-carboethoxy) ethyl radicals. The calculated molecular weightof mono-ethyl mono-oleyl fumarate having 1.52 of thebis(1',2-carboethoxy)ethyl radicals is 656.7; found, 644.5 by molecularweight determination in benzene; calcd. saponification equivalent 131.3;found, 136.1;

and the found free acid content of the 1.52 adduct is 1.06%.

Exdntple 3 Sixty parts of polyvinyl chloride and 40 parts by weight ofthe butyl ester of Example 1 were mixed on a rolling mill to ahomogeneous blend. During the milling there was observed substantiallyno fuming and discoloration.

A molded sheet of themixture was clear and transparent and substantiallycolorless. for low temperature flexibility, according to the testingprocedure described above, gave a value of minus 43 C. which valuedenotes good low temperature properties. Tests on the volatilitycharacteristics of the plasticized composition gave a value of 2.98percent. The plasticized material had a hardness of 78 before thevolatility test and a hardness of 78 after the volatilitytest. Whensubjected to heat at a temperature of 325 F. for a period Testing of themolded sheet of 30 minutes the clarity and color of the molded productwere substantially unchanged. Tests of the waterresistance properties ofthe plasticized material employing the test procedure described aboveshowed a solids-loss of only 0.13 percent and an 0.45 percent waterabsorption value.

Example 4 Employing the evaluation procedure of Example 3, the ester of-Example 2 was tested as a plasticizer for polyvinyl chloride. The lowtemperature flexibility value thus obtained was minus 0.5 C., and thevolatility value was 0.45 percent, which value denotes extremely goodvolatility properties. The plasticized material had a hardness of 92before the volatility test and a hardness of 92 after the volatilitytest. Water-resistance tests gave a solids-loss value of only 0.03percent and an 0.35 percent water absorption value.

Instead of the esters employed in the above examples, other estersobtained by the reaction of alkenyl esters with the present acyclicdicarboxylates give similarly valuable plasticized polyvinyl chloridecompositions. Thus, by employing 40 parts by weight of the diethyl ordihyexyl (l',2'-dicarboxyethyl)oleyl butyrate, the diisoamyl or dimethyl(l,2'-dicarboxyethyl)undecenyl n-hexoate or the cross-esterifiedaddition products obtained by reaction of undecenyl acetate with dihexylfumarate or diethyl citraconate, with 60 parts of polyvinyl chloride orwith 60 parts by weight of a vinyl chloride-vinyl acetate copolymerknown to the trade as Vinylite, there are obtained clear, colorless,compositions of very good flexibility and stability.

While the above examples show only compositions in which the ratio ofplasticizer to polymer content is 40:60, this ratio being employed inorder to illustrate comparable efliciencies, the content of ester topolyvinyl chloride may be widely varied, depending upon the propertiesdesired in the final product. For many purposes a plasticizer contentof, say, from only percent to percent is preferred. The present estersare compatible with polyvinyl chloride over wide ranges ofconcentrations, up to 50 percent of esters based on the total weight ofthe plasticized composition yielding desirable products.

Although the invention has been described particularly withreference tothe use of the present esters as plasticizers for polyvinyl chloride,these esters are advantageously employed also as plasticizers forcopolymers of vinyl chloride, for example, the copolymers of vinylchloride with vinyl acetate, vinylidene chloride, methyl methacrylate,acrylonitrile, etc. Preferably, such copolymers have a high vinylchloride content, i. e., a vinyl chloride content of at least 70 percentby weight of vinyl chloride and up to percent by weight of thecopolymerizable monomer.

The plasticized polyvin l halide compositions of the present inventionhave good thermal stability; however, for many'purposes it may beadvantageous to use known stabilizers in the plasticized compositions.Inasmuch as the present esters are substantially unreactive with thecommercially available heat and light stabilizers which are commonlyemployed with polyvinyl chloride or copolymers thereof, the presence ofsuch materials in the plasticized products does not impair the valuableproperties of the present esters. The present esters are of generalutility in softening vinyl'chloride polymers. They may be used as theonly plasticizing component in a compounded vinyl chloride polymer orthey may be used in conjunction with other plasticizers.

This application is a division of my application Serial No. 181,947,filed August 28, '1950, now Patent No. 2,782,227.

What I claim is:

l. A resinous composition .comprising a vinyl chloride polymerplasticized with a polycarboxylate having the general formula:

in which T is an alkenyl radical of from 9 to 23 carbon atoms, Y isselected from the class consisting of hydrogen and the methyl radical,alk is an alkyl radical of from 1 to 6 carbon atoms, X is selected fromthe class consisting of alk and the radical -CY:CY.COO.alk, and n is anumber of from 1 to 3.

2. A resinous composition comprising polyvinyl chloride plasticized witha polycarboxylate having the general formula:

in which T is an alkenyl radical of from 9 to 23 carbon atoms, Y isselected from the class consisting of hydrogen and the methyl radical,alk is an alkyl radical of from 1 to 6 carbon atoms and X is selectedfrom the class consisting of alk and the radical --CY:CY.COO.alk, and nis a number of from 1 to 3.

3. A resinous composition comprising a copolymer of at least 70 percentby weight of vinyl chloride and up to 30 percent by weight of anunsaturated monomer copolymerizable therewith, said copolymer beingplastic.- ized with a polycarboxylate having the general formula:

T.CHzOOC.X Y.( 3.000.alk [Y.( 3H.C00.alk],. in which T is an alkenylradical of from 9 to 23 carbon atoms, Y is selected from the classconsisting of hydrogen and the methyl radical, alk is an alkyl radicalof from 1 to 6 carbon atoms, X is selected from the class consisting ofalk and the radical -CY:CY.COO.alk, and n is a number of from 1 to 3.

4. A resinous composition comprising polyvinyl chloride plasticized withdibutyl (l',2-dicarboxyethyl)- octadecenyl acetate.

5. A resinous composition comprising polyvinyl chloride plasticized withmono-ethyl mono-oleyl fumarate in which from 1 to 3 hydrogen atoms ofthe oleyl radical are substituted by a (l',2-dicarboethoxy)ethylradical.

No references cited.

1. A RESINOUS COMPOSITION COMPRISING A VINYL CHLORIDE POLYMERPLASTICIZED WITH A POLYCARBOXYLATE HAVING THE GENERAL FORMULA: